Re-instate manwar's first PR
Re-instate manwar's first PR

With some more tweaks: using unexpected named parameters on "plan" should
now cause a run time error rather than silently ignoring them.

MasterDuke17/rakudo,labster/rakudo,tony-o/rakudo,MasterDuke17/rakudo,nbrown/rakudo,rakudo/rakudo,labster/rakudo,Gnouc/rakudo,nbrown/rakudo,salortiz/rakudo,MasterDuke17/rakudo,labster/rakudo,Gnouc/rakudo,Gnouc/rakudo,tbrowder/rakudo,labster/rakudo,labster/rakudo,nbrown/rakudo,MasterDuke17/rakudo,tony-o/rakudo,rakudo/rakudo,softmoth/rakudo,tony-o/rakudo,rakudo/rakudo,nbrown/rakudo,rakudo/rakudo,tony-o/rakudo,rakudo/rakudo,salortiz/rakudo,tbrowder/rakudo,Gnouc/rakudo,MasterDuke17/rakudo,softmoth/rakudo,salortiz/rakudo,nbrown/rakudo,softmoth/rakudo,salortiz/rakudo,nbrown/rakudo,softmoth/rakudo,rakudo/rakudo,labster/rakudo,tony-o/rakudo,tbrowder/rakudo,tbrowder/rakudo,Gnouc/rakudo,MasterDuke17/rakudo,tbrowder/rakudo,Gnouc/rakudo,salortiz/rakudo,tony-o/rakudo,softmoth/rakudo,tbrowder/rakudo,salortiz/rakudo